Não informado. (1971). Environmental Health Review. Canadian Institute of Public Health Inspectors.
Chicago-referens (17:e uppl.)Não informado. Environmental Health Review. Ontario, Canada: Canadian Institute of Public Health Inspectors, 1971.
MLA-referens (8:e uppl.)Não informado. Environmental Health Review. Canadian Institute of Public Health Inspectors, 1971.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.